Well I would say its a little of both! In the movie Matt was genuinely a nice guy and even though Kelly beat him up, took his girl, drugged him and what not, there was no grudge on Matt's part as he eventually gets Danielle, goes to Princeton and ends up making a lot of money too.

But that shouldnt stop someone from having the last laugh, ryt?! And if you remember, Kelly's smirk on reading the note was more of like an involuntary 'tip of the hat'.